I just found this page: http://www.dainile.lt/?p=540 Via Google Translate I was able to understand it: that device (similar / same to mine) seems to be a dedicated device to open a URL (under Windows), where the URL is in an EEPROM

"And now about the operation - when connected to a USB key Windows'am it presents itself as a HID device with a keyboard function (Amendment ), which runs the Run (Win + R), and as I told you record the page address and numyga ENTER"

So in that way it indeed acts as a keyboard ...

Strangely enough, nothing happens in my terminal when I plug the device in.
And I can't find a device /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.2/1-1.2:1.0/input/input19 ...

EDIT: The commerical name seems to be "USB Webkey", used for promotional / marketing activities. ... Ah, there is even such an URL http://www.webkey.com/ (warning: that's a commercial site)